I know this is the wrong place to discuss this, but it has already been raised in the right place with no successful resolution, so I am going to try here and hope I don't get flamed too badly. Basically, the admin menu admin/user/permissions has stopped working. I can check tickyboxes and hit submit, but none of my changes take effect.
As described in the linked thread, using the admin/user/roles menu to edit permissions is successful. I am using a Zen subtheme, but changing to Garland did not help. It's Drupal 6. As far as I can tell the Drupal error logs are not showing me anything interesting.
Have any of you run into this situation? If not, what tools should I use to troubleshoot the situation?